Prevention of liver failure in parenteral nutrition-dependent children with short bowel syndrome

Prevention of parenteral nutrition-associated liver disease in children

Liver injury is associated with parenteral nutrition therapy. Severity of injury varies from minimal and transient increases in liver-related blood tests to biliary cirrhosis and liver failure. Severe parenteral nutrition-related liver disease is usually confined to patients who have undergone massive intestinal resection. In these patients, early sepsis appears to cause initial liver injury, and recurring sepsis and inflammation, local or systemic, may result in its perpetuation and progression. Liver disease associated with parenteral nutrition is not necessarily related either to duration of parenteral nutrition or to delayed intestinal feeding. However, treatment includes enteral nutrition to promote enterohepatic circulation of bile acids and management of inflammation and sepsis, including control of intestinal bacterial overgrowth. Restriction of intravenous lipid emulsions may be important. The clinical picture of advanced liver failure related to short bowel syndrome differs from liver failure with an anatomically normal gastrointestinal tract. In the former, hyperbilirubinemia, hepatosplenomegaly, and functional hypersplenism dominate the clinical picture, and severe ascites and esophageal variceal hemorrhage are unusual. Early referral of these patients for intestinal and/or liver transplantation may provide the best chance for long-term survival.

Short bowel syndrome in infants and children: an overview

Short bowel syndrome is a spectrum of malnutrition resulting from inadequate bowel length. In infant and pediatric patients, the most common causes are necrotizing enterocolitis, abdominal wall defects, jejunal ileal atresia, and mid gut volvulus. There appear to be regional variations in etiology. Since the publication of Wilmore's classic monograph in 1972, there have been significant improvements in monitoring and nutritional support. In the modern era, survival rate ranges from 80% to 94%, and the presence or absence the ileal cecal valve appears to not impact on mortality rate, but does significantly affect the length of time on total parenteral nutrition TPN. The most common morbidities remain sepsis, both central line related and bacterial overgrowth, and TPN cholestasis. Long-term recovery of these children often is remarkably normal, but there is a 10% to 15% incidence of neurologic and developmental defects. The clinical and ethical considerations around the care of infants with 20 to 40 cm of residual bowel remains controversial, as does the place of intestinal transplantation, especially in patients developing gut failure in infancy. Perioperative surgical decision making plays a critical role in the long-term outcome of these patients. This chapter presents an overview of the current status of care and outcome in this difficult population; these topics are further expanded in subsequent chapters.

Abnormal liver function tests in a patient fed with total parenteral nutrition and treated with octreotide

Octreotide is a long-acting analog of somatostatin, a hypothalamic release-inhibiting hormone. It is sometimes used therapeutically to relieve symptoms associated with acromegaly and gastroenteropancreatic endocrine tumors. It has also been used in the treatment of short-bowel syndrome and gastrointestinal and biliary fistulae. We report a patient with biliary leakage due to Marizzi's syndrome treated with total parenteral nutrition and octreotide who developed abnormal liver function tests that improved when the two treatments were stopped. We also review the literature regarding abnormal liver function tests in patients on total parenteral nutrition.

Total parenteral nutrition-associated intrahepatic cholestasis in infants: 25 years' experience

BACKGROUND/PURPOSE

There are few long-term chronological reviews examining the incidence of total parenteral nutrition (TPN)-associated intrahepatic cholestasis (TPNAC) in infants. The authors therefore reviewed TPNAC in their 25-year series, and also looked at the current problems associated with TPN in infants.

METHODS

Two hundred seventy-three surgical neonates who received TPN for more than 2 weeks were divided into 3 groups chronologically: group A (1971 through 1982, n = 77), group B (1983 through 1987, n = 72), and group C (1992 through 1996, n = 124). TPNAC was defined as serum direct bilirubin (DB) level greater than 2.0 mg/dL during the neonatal period.

RESULTS

The incidence of TPNAC in groups A, B and C was 57%, 31%, and 25% (P< .01), respectively, and the mortality rate from TPN-associated complications was 13%, 3%, and 3% (P< .05), respectively. Over the last 5 years, severe TPNAC developed in 20 patients (16%). Four of 20 died of TPN-associated sepsis with hepatic failure; 2 had hypoganglionosis with intractable stagnant enteritis and subsequent sepsis, and 2 had fatal respiratory or cardiac disease.

CONCLUSIONS

The incidence of TPNAC in surgical neonates and TPN-associated mortality rates have decreased significantly. The mortality rate, however, still remains at 3%. Two of 4 fatal cases had hypoganglionosis, which were totally dependent on TPN. In patients who require long-term TPN, TPN still has unsolved problems, and small bowel transplantation may be indicated.

Effect of growth hormone, epidermal growth factor, and insulin on bacterial translocation in experimental short bowel syndrome

BACKGROUND/PURPOSE

An adaptive process starts in the remaining intestine after massive resection, and several trophic factors including growth hormone (GH), epidermal growth factor (EGF), and insulin (INS) have been shown to have a positive effect on it. Bacterial translocation (BT) is frequent after extensive small bowel resection, but the effects of GH, EGF, or INS have not been investigated in experimental short bowel syndrome (SBS). This study tests the hypothesis that GH, EGF, or INS decrease BT in SBS in rats with parenteral nutrition (PN).

METHODS

Thirty-eight adult Wistar rats underwent central venous cannulation and were assigned randomly to 1 of 4 groups receiving for 10 days 4 treatment regimes: (1) PN group (n = 10): fasting, all-in-one PN solution (300 mL/kg/24 h, 280 kcal/kg/24 h), 80% gut resection including ileo-cecal valve; (2) GH group (n = 9): fasting, same PN regime and resection, GH (1 mg/kg/d, subcutaneously); (3) EGF group (n = 9): fasting, PN, resection, EGF (150 microg/24 h intravenously); (4) INS group (n = 9): fasting, PN, resection, INS (1 UI/100 g/24 h subcutaneously). At the end of the experiment they were killed, and mesenteric lymph nodes (MLN) and peripheral and portal blood samples were recovered and cultured. Several fragments of intestine were taken to determine cell proliferation (PCNA index) and morphometric parameters (villous height, crypt depth).

RESULTS

GH, EGF, and INS groups showed a 28%, 29%, and 30% increase in gut mucosal thickness, and PCNA index rose 21%, 20%, and 25%, respectively in comparison with PN controls. Bacterial translocation to peripheral blood was detected in 0% of PN animals and in 44%, 40%, and 28% of GH, EGF, or INS rats, respectively (P < .05). No differences were found in BT in MLN or portal blood among groups.

CONCLUSION

Administration of GH, EGF, or INS improves gut mucosal structure in rats with SBS under PN, but, surprisingly, the incidence of BT detected in peripheral blood was increased rather than decreased in animals receiving these treatments.

Management of cholestasis in infants with very low birth weight

Infants with very low birth weight (VLBW) are at increased risk of cholestasis when compared with older infants and children. Factors associated with this increased risk of cholestasis include immaturity of the biliary excretory system, a diminished immune response to sepsis, an increased incidence of necrotizing enterocolitis and short bowel syndrome, as well as an increased exposure to parenteral nutrition (PN). The current literature on cholestasis in VLBW infants and the factors that mediate the initiation and progression of cholestatic liver damage is reviewed. A protocol for managing infants with cholestatic jaundice is presented, and a case report is included that shows use of the protocol to normalize the bilirubin in a VLBW infant with severe cholestatic jaundice.

Long-term outcome of short bowel syndrome in adult and pediatric patients

We reviewed 12 pediatric and 18 adult patients with short bowel syndrome (SBS) from Osaka University Hospital and compared clinical characteristics between them. The length of the residual small intestine ranged from 0 to 75 cm (mean 47 cm) in pediatric patients and from 0 to 150 cm (mean 47 cm) in adult patients. In all cases, total parenteral nutrition (TPN) was started immediately after surgery and was gradually replaced by enteral nutrition. Eight pediatric patients (67%) and 4 adult patients (22%) were weaned from TPN. Residual intestinal length in these patients ranged from 27 to 75 cm (mean 57 cm) in pediatric patients and 57 to 150 cm (mean 96 cm) in adult patients. Pediatric patients with residual small intestinal lengths of 0, 16, 25, and 45 cm were not weaned from TPN. None of the adult patients with residual small intestinal length less than 40 cm could achieve complete intestinal adaptation. Five adult patients died due to liver failure (2 cases), heart failure (2 cases), or pneumonia (1 case), whereas all pediatric patients survived. The average life span of indwelling central venous catheters was 511 days and 780 days, and the rate of catheter-related sepsis per 1000 catheter days was 0.73 and 0.48 in pediatric and adult patients, respectively. Plasma levels of arginine and citrulline in patients receiving TPN were significantly decreased compared with those in patients receiving TPN without SBS both in pediatric and adult patients (p < .01). These results indicate that pediatric and adult patients with SBS can survive with TPN and enteral nutrition. The minimum remaining intestinal length necessary for complete bowel adaptation is shorter for pediatric patients than adults, suggesting better bowel adaptation in pediatric patients.

New approaches to understanding the etiology and treatment of total parenteral nutrition-associated cholestasis

Total parenteral nutrition-associated cholestasis (TPN-AC) may be a fatal disease. The only known effective treatment is to discontinue TPN and institute full enteral feedings. However, this is not possible for many patients with severe gastrointestinal failure. Current research supports two theories regarding the etiology of TPN-AC. One proposes that the enteral fast disrupts the enterohepatic circulation. Cholestasis, in this hypothesis, results from a combination of altered gut hormone production and endotoxins produced by bacterial translocation. The second theory implicates the direct toxicity of TPN solution. Amino acid solutions and plant sterols in intralipid have generated much interest. Ursodeoxycholic acid and S-adenosyl-L-methionine are promising treatments for TPN-AC. They have been proven to be effective in animals and adult liver diseases. Cholecystokinin also has been investigated as a possible prophylactic agent. However, results from these experiments do not conclusively show a beneficial effect.

Incidence, prognosis, and etiology of end-stage liver disease in patients receiving home total parenteral nutrition

BACKGROUND

Elevations in liver function tests have been reported in patients receiving total parenteral nutrition (TPN). The clinical aspects of end-stage liver disease (ESLD) associated with the prolonged use of home TPN have not been fully clarified. In previous series patients with duodenocolostomies appeared to be at higher risk than persons with some jejunum or ileum remaining in situ.

METHODS

The records of 42 patients treated with home TPN for more than 1 year were examined. This constituted 283 person-years of home TPN. Patients with duodenocolostomies were examined as a separate group on the basis of the literature experience.

RESULTS

Six of 42 patients who received chronic home TPN had ESLD with 100% subsequent mortality, at an average of 10.8 +/- 7.1 months after the initial bilirubin elevation. Thirteen of 42 patients had superior mesenteric artery or vein thrombosis (SMT) leading to duodenocolostomy. In 8 of these 13 patients with SMT and underlying inflammatory or malignant disorder, 2 had ESLD. The remaining 5 SMT patients who had only minimal liver enzyme elevation over 13.6 +/- 6.7 (range 3 to 19) years of home TPN were significantly younger (36 +/- 7 years vs 64 +/- 13 years) and did not have underlying inflammation either by clinical diagnosis or as reflected in the high normal serum albumin level (> or = 4.0 g/dL). Despite their extreme short bowel syndrome and long exposure to home TPN, ESLD did not develop.

CONCLUSIONS

Approximately 15% of patients who receive prolonged TPN have ESLD with a high rate of morbidity and mortality. The combination of chronic inflammation and the short bowel syndrome appears to be necessary for the development of ESLD with prolonged home TPN.

Discontinuous total parenteral nutrition prevents postischemic mitochondrial dysfunction in rat liver

Although discontinuous total parenteral nutrition (d-TPN) has recently been favored for clinical use over continuous total parenteral nutrition (c-TPN) to ameliorate liver dysfunction, mechanisms for the protection against postoperative liver dysfunction remain unknown. This study aimed to examine differences in mitochondrial function in d-TPN- and c-TPN-pretreated livers during ischemia-reperfusion. Rat livers pretreated with d-TPN or c-TPN were perfused with Krebs-Ringer buffer and were exposed to 25% low-flow hypoxia followed by reperfusion. Intrahepatic mitochondrial membrane potential (triangle up) and cell viability were assessed by dual-color digital microfluorography using rhodamine 123 (Rh123) and propidium iodide (PI), respectively. In response to hypoxia, livers pretreated with c-TPN, d-TPN, and an ordinary chow diet exhibited a significant triangle up reduction among the entire lobules. Upon reperfusion, the regional triangle up values further decreased in the c-TPN liver, whereas those in the d-TPN-treated or chow-treated livers displayed a rapid recovery toward the control levels. The severity of cell injury did not differ among the groups, showing that the reperfusion-induced triangle up drop in the c-TPN-pretreated liver is not a consequence of cell injury. Differences in the triangle up drop among the groups appear to occur irrespective of those in the glycogen storage, because the livers undergoing d-TPN display a marked triangle up recovery even when reperfused at the end of a fasted state. These results indicate that c-TPN, but not d-TPN, jeopardizes mitochondrial re-energization and suggest that a circadian pattern of the TPN serves as a potentially beneficial strategy to reduce the risk of postischemic mitochondrial dysfunction in the liver.

Advances in neonatal surgery

Neonatal surgery has reached a high degree of sophistication. We are now entering a new era of widespread screening of the unborn by means of ultrasound, with planned intrauterine, intrapartum, and immediate postpartum interventions. Many pediatric surgical centers are now focusing their investigative efforts on elucidating the cellular, molecular, and biochemical response to disease and therapeutic agents. The author presents the topic of neonatal surgery to some of the newer applications, techniques, and approaches.